FIRST: You used the incorrect form of speech in the first sentence. The one you must use in correct grammar is the word "too". The word "to", however, is an infinitive verb or a preposition.
SECOND: There needs to be a comma before the word "granny".
THIRD: As you are utilizing the word "granny" to address me, the "g" needs to be capitalized.
FOURTH: "Em" is a contraction, so needs a leading apostrophe.
The correct grammatical form of your post should read:
"You got balls too, Granny? I'll suck 'em."
Next time, work on your grammar.